I have never had an issue with any logic board, desktop or notebook.
I have had a PowerBook 1400cs, PowerBook 520, 2 PowerBook G3 (Wallstreet), 1 PowerBook G3 (Lombard), an iBook G4, an iBook G3 (ice) and the PowerBook G4 I have now.
I have also had 3 iMac G3's, an eMac, a B&W Power Mac G3, a Power Mac G5, and a few random clones over the years.
Not a single one of those machines has ever had a problem with the logic boards, though some of those machines were supposedly "plagued" by continual issues with them.

No computer is "designed to fail". Only snobby tech-hounds really fall for that mentality and believe something ludicrous like that to be the honest, given truth. It is one of the ways they can justify 'needing' the latest and greatest technology.

mac: a waterproof raincoat made of rubberized fabric
MAC: a data communication protocol sub-layer, also known as the Media Access Control
Mac: a brand name which covers several lines of personal computers designed, developed, and marketed by Apple Inc.

I challenge you to go out to a Toyota forum and search for the terms "engine failure". See how many posts you come up with - I'll bet it's in the hundreds.

Does that mean that Toyotas have a problem with chronic engine failure? Absolutely not, Toyota is probably one of the highest ranked automotive manufacturers out there in terms of reliability and quality. In their own industry, so too is Apple.

The reason for the number of posts is simple. People come to web forums to complain when they have a problem and are generally far less apt to come to a forum solely to praise their reliability.

To put it simply, web forums are not a good gauge of product reliability.

Liquid and computers don't mix. It might seem simple, but we see an incredible amount of people post here about spills. Keep drinks and other liquids away from your expensive electronics!